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- Thread starter Shovelrick
- Start date
kmakar
Janitor
That's what I do. I have a vac gauge and it gets me spot on every time.
I have a vac gauge mounted on the hood grill and that’s how it’s adjusted now, I pushed a vac hose through the chrome grill, attached it to the gauge then tie strapped it, looks Red Neck but does what it’s meant to do 
my 65 Impala SS had a factory vac gauge
my 65 Impala SS had a factory vac gauge
Here’s a pic 
So the A/F gauge is more for adjusting for cruise fuel usage ?
Tomorrow I’m going to put it back inside the car, put the sensor on Drv side then go for a drive
Looks like I’ll need to get a box of different size Holley parts
Your carb came with front jets 78 and rear 82. Power valve was 4.5.Looks like I’ll need to get a box of different size Holley parts
The primary nozzle was .040 and that's what your spec sheet says it still is.
It may be that something isn't working right ; needle and seat stuck open ?
I would clean it, check the floats, adjust the idle and take readings with the O2 sensor.
That should tell you what needs to be adjusted. I wouldn't buy any parts until you get some readings at idle, cruise and WOT.
Holley 0-80531 850 CFM Classic Holley Carburetor
Classic Holley carbs have been a staple for rodders around the world for decades. They're the perfect performance upgrade for stock to mildly modified vehicles and have that classic Holley look. Holley's 0-80531 has the perfect calibration for GM's 502 crate engine. Dual feed fuel inlets...
www.holley.com
These are the ranges you are shooting for.
- Cruise: 14.7:1 - 15.5:1
- Idle: 13.5 - 15.0
- Wide-open throttle: 11.5:1 - 13.3:1
How To Tune The Power Valve In A Holley Carburetor
How to ensure your Holley carburetor is using the right power valve for your engine. Holley carburetors have a power enrichment system that provides fuel to the main power circuit during heavy loads or under full throttle situations. The vacuum operated power enrichment system is controlled by a...
www.holley.com
That spec sheets for the 850 I have not the 1,000 but I’m going to buy a box of different size jets etc and at least try rebuilding the 850 myself but I’m still thinking of having a pro rebuild the 1,000Your carb came with front jets 78 and rear 82. Power valve was 4.5.
The primary nozzle was .040 and that's what your spec sheet says it still is.
It may be that something isn't working right ; needle and seat stuck open ?
I would clean it, check the floats, adjust the idle and take readings with the O2 sensor.
That should tell you what needs to be adjusted. I wouldn't buy any parts until you get some readings at idle, cruise and WOT.
Holley 0-80531 850 CFM Classic Holley Carburetor
Classic Holley carbs have been a staple for rodders around the world for decades. They're the perfect performance upgrade for stock to mildly modified vehicles and have that classic Holley look. Holley's 0-80531 has the perfect calibration for GM's 502 crate engine. Dual feed fuel inlets...
I think if I got in a carb with a drill bit that would be "All She Wrote" for the poor carb 